This invention relates to improved centrifugal pumps and to systems using such pumps.
More particularly, the present invention relates to the type of centrifugal pump that includes an impeller or rotor which is rotated in moderately close proximity to a stationary plate or stator. The stationary plate has a central, coaxial inlet through which liquid passes and is thereafter conveyed by centrifugal force along the impeller-plate spacing to an outlet at the periphery of the impeller and the plate.
One type of centrifugal pump as described immediately above is shown and claimed in U.S. Pat. No. 3,907,456 issued to the inventor hereof. In the '456 patent, pumping efficiency is improved by creating complementary sinuous surfaces on the impeller and the plate. The impeller may carry sinuous vanes complementary to both surfaces which radiate outwardly to the impeller's periphery and define flow passages therebetween.
The pump of the '456 patent itself was an improvement of earlier centrifugal pumps which typically included very close spacing between the impeller and the plate. Prior to '456 patent the surfaces of both the impeller and the plate had typically been smooth. Prior art centrifugal pumps are shown in the following U.S. Pat. Nos. 1,013,248; 1,383,937; 2,569,563, 2,737,898; and 2,780,176.
The pump of the '456 Patent permits efficient pumping operation while producing an extremely low absolute pressure at the inlet. Indeed, the centrifugal pump of the '456 Patent is capable of pumping gasses or vapors as well as liquids, and, thus, is a true fluid (liquid and/or gas) pump.
A primary object of the present invention is to further improve the pump of the '456 Patent by improving its performance characteristics and also, to provide for a modification of the pump of the '456 Patent to permit it to be used in a novel fashion to achieve hitherto unrealized results including the desalinization of sea water, and the production of water-oil emulsions for combustion in oil furnaces or the like and de-gassification of liquids.